Fiction, by its very definition, isn't real. A character can have an entire lifetime of backstory, the politics and geography of their made-up homeworld a matter of record, but none of it would exist if writers, actors, artists and other creatives hadn't imagined it first. Pretend a pivotal moment from their past never happened, and history isn't actually being rewritten. A hero isn't going to sue anyone for defamation if they're suddenly reappraised as a villain.
Yet it sometimes feels as if sci-fi and fantasy "canon" in sci-fi and fantasy is the most sacred of sacred cows. Movies and TV shows frequently tie themselves in knots trying to avoid contradicting throwaway lines of dialogue uttered decades earlier. Fans — and I'll admit I've been as guilty of this as anyone — have always been happy to flag up inconsistencies in franchise lore, while the Marvel Cinematic Universe has built its entire brand on labyrinthine continuity. Lucasfilm even employs its own "Keeper of the Holocron" to stay on top of the vast timeline of a galaxy far, far away.
